EPA hesitates to allow waste water disposal in Madison Aquifer

The Environmental Protection Agency is asking for more information from Encana before it okays an aquifer exemption allowing the company to pump waste water into the Madison aquifer near Casper.

Last month, The Wyoming Oil and Gas Conservation Commission voted to allow the exemption, but Monday, the EPA sent the Commission a letter saying that the conceptual model of the well appears to be too broad. The letter goes on to say that such a generalized model will not be able to accurately evaluate “the fate of the plume” and recommends that the model be modified to better reflect the local hydrologic and hydrogeologic conditions in the area.

Encana asked for the exemption based on the conviction that that particular part of the aquifer is economically and technologically impractical to use for drinking water, but the EPA says Encana does not make a case as to why that is.

E-P-A needs to approve Encana’s plans before they can start using their injection well. For Wyoming Public Radio, I’m Irina Zhorov.